Cryosurgery has a wide range of uses in medicine and dentistry. However, in-vivo studies that demonstrate the exact sequence of repair and regeneration of tissues subjected to low temperatures are few in number. Also, standardized experimental models for comparison of different techniques of cryosurgery remain to be developed. A two-year program is proposed. Two intraoral sites, the posterior hard palate and base of the tongue and the submandibular gland would be subjected to freezing in situ utilizing the Rhesus monkey. The tissue response would be evaluated at intervals up to one year. The basis of the evaluation would consist of site analysis with the light and electron microscope. These findings would be correlated with carbohydrate, lipid, enzyme, and neural histochemistry. This approach should provide meaningful data pertaining to the mechanism of cell death from freezing and possible altered function of cells which survive freezing.